Cracking
A cracking sound when moving the knee can have a variety of causes. Possible air inclusions in the synovial fluid, cartilage damage, damage to the ligaments, overloading of the joint or even arthrosis of the knee joint can be the cause of a cracking of the knee joint. The most common cause of such cracking is age-related wear and tear of the cartilage and bones in the knee.
The crunching or cracking sound is therefore often an indication of damage to the cartilage or signs of wear and tear. The constant bending and stretching movements lead to heavy strain on the joint and joint surfaces. In addition, the entire body weight is placed on this joint.
The cracking can also be caused by increased, excessive sport. Athletes are therefore affected much more often than people who do little or no sport.Recent knee injuries such as torn cruciate ligaments or injuries to the menisci can also lead to cracking or snapping, which is often accompanied by knee pain. The pain then occurs mainly during bending movements of the knee joint.
If the crackling occurs after a fall or possible injury to the knee joint, it is advisable to consult a doctor directly. Under no circumstances should you wait to see if the noise goes away again. You should also see a doctor if the cracking in the knee is associated with knee pain and swelling of the knee.
No matter what type of knee pain you suffer from, you should still observe the following principles. It is always important to know what the knee pain is like. A distinction is made as to whether the pain is rather stabbing, pulling, pressing, permanent or only of very short duration.
The exact location of the pain is equally important. A distinction is made between front, back and lateral knee pain. An indication of the cause can also be the situation when the pain occurs.
In this case, a distinction is made between pain at rest and pain that only occurs when the patient is under stress. Internal knee pain can be treated conservatively without surgery or minimally invasively by means of knee arthroscopy or major surgery. The choice of therapy depends on the cause of the pain, the degree of damage, the corresponding knee structure and the wishes of the patient.
For example, the pain can occur due to overstrain after jogging. No acute treatment is required here, a rest is sufficient to let the inner knee pain subside again. The situation is completely different with a torn inner meniscus.
The treatment of a torn inner meniscus depends entirely on the age, mobility and sporting activity of the patient. In the case of a slight tear, an attempt can first be made to treat the resulting inner knee pain by means of sparing. In addition, the patient should always take advantage of physiotherapy in order to maintain the mobility of the knee joint even after the injury.
It is also important that the patient puts little strain on the knee when suffering from inner knee pain. Therefore, walking on crutches for a short time is a suitable treatment measure. If an inflammation of the joint occurs due to a torn inner meniscus, the patient can treat the inner knee pain with anti-inflammatory drugs, so-called non-steroidal anti-rheumatic drugs (NSAIDs) and cooling.
If the torn meniscus is too deep or too severe, it may be necessary to perform a partial meniscectomy. This treatment of the inner knee pain caused by the torn meniscus should always be the last option. In order to reach the inner meniscus, a mirror image (a so-called arthroscopy) of the knee joint must be taken.
The surgeon makes at least two small incisions next to the kneecap, through which a camera and tools can be introduced into the knee joint. This minimally invasive approach can be used to treat not only the menisci, but also the cruciate ligaments or mucous membrane folds. The advantage is that patients recover much faster and a good cosmetic result is achieved.
In addition, the rate of wound infections is significantly reduced compared to large open operations. Among the complications, in addition to unsuccessful surgery, thrombosis is the most common. However, the risk is considered low, at less than 1%.
As a preventive measure, heparin abdominal injections should be administered until the knee can be fully loaded again. If a rupture of the inner meniscus is detected during the endoscopy due to inner knee pain, it will be treated immediately. It depends on the area where the tear is located.
The cartilage that makes up the meniscus is only well supplied with blood vessels at the base of the knee joint. This means that a suture of the meniscus is successful for tears close to the base. After the operation, the knee joint must first be held still with an extension splint.
For about 3 weeks crutches should be used to avoid full weight bearing of the knee. The flexion is slowly restored during physiotherapy, but the patient should be prepared not to practice any strenuous sports for up to three months. Overall, the number of meniscus tears that can be treated with sutures is low, but the prognosis is very good.In the case of tears that are further away from the base, the blood supply is insufficient for the cartilage to heal.
In this case a partial meniscus resection is performed. The torn part of the meniscus that causes the inner knee pain is removed. Since the meniscus does not have to heal, the knee can be loaded normally much earlier.
Usually, only small pieces of the meniscus are removed, otherwise there is a risk of early arthrosis of the knee joint. An injury in which the inner meniscus is also involved is the Unhappy Triad. In addition to the inner meniscus and the inner collateral ligament, the anterior cruciate ligament is also affected.
The inner meniscus is treated as described above in a knee joint endoscopy. In addition, the anterior cruciate ligament is also replaced here. Usually, a piece of tendon is removed from the inner side of the thigh and attached to the knee joint as a new cruciate ligament.
If the inner meniscus does not need to be treated, the swelling is waited for about 4 weeks until it has subsided and the knee is examined again. At this stage it can be decided whether the stability of the knee joint is sufficient for the physical activity of the patient and therefore does not need to be operated. On the other hand, delayed interventions on the cruciate ligament have a slightly better prognosis with regard to functionality.
Aftercare includes gentle physiotherapy and relief with crutches. After about four months, sports can be started carefully. Tears of the inner ligament as a cause of inner knee pain can be treated conservatively in most cases.
After the accident, the knee should be immobilized. The doctor usually prescribes a splint (also called an orthosis) for this purpose, which is worn for six weeks. During this time the inner ligament can stabilize itself sufficiently.
It can take three months before movement is completely restored by physiotherapy. If there is still a feeling of instability afterwards or the patient’s level of sporting activity is very high, the tendon can also be sutured through a small incision. However, this is more likely to be recommended for combination injuries such as the Unhappy Triad.
Another option for treating internal knee pain is minimally invasive surgery, in which the cruciate ligament is removed and usually replaced by a tendon of a muscle (for example, the semitendinosus muscle). Since the new cruciate ligament cannot be fully loaded again immediately, it takes a little longer before this treatment for inner knee pain takes effect. Since the plica mediopatellaris is a fold of mucous membrane that has no function for the knee, it can be removed without any problems during a knee arthroscopy.
The fold is placed directly at the level of the joint capsule, so that no parts can be trapped during movement. Here, too, the strain must then be relieved using crutches until the knee can be loaded again without pain. With the exception of knee joint replacement, arthrosis cannot be cured.
However, there are numerous possibilities to stop or at least slow down the course of the degenerative disease and thus eliminate the pain. The first step in treatment is conservative therapy. This includes in particular movement without putting strain on the knee joint.
Especially swimming and cycling are good sports to keep the joint in motion. Sports that involve rapid, abrupt changes of direction and heavy strain on the knee joint, such as squash or soccer, are not recommended. Overweight should also be reduced, as the additional body weight further overloads the already damaged knee.
During physiotherapy or knee training, which is often offered by health insurance companies, professionals teach patients exercises that they can perform at home to further promote the mobility of their joint. In consultation with the doctor, it is also advisable to take so-called anti-inflammatory drugs. These are painkillers such as ibuprofen or diclofenac, which not only reduce pain but also reduce inflammation of the diseased joint.
Using ointments with these ingredients or applying compresses can also provide relief. Especially if there is an axial malposition of the leg, an adjustment with insoles is possible. In the case of internal knee pain, the patient often has a bowed leg.
By raising the sole of the shoe on the outside, this can be partially compensated.The next therapeutic step is the application of cold in the form of cryotherapy or heat therapy. In the early stages of arthrosis, heat has a pain-relieving effect. However, as soon as the arthrosis is activated, i.e. when an inflammation has developed due to the loss of cartilage, cold instead of heat should be applied.
An alternative to heat therapy is electrotherapy, in which medium-frequency currents are applied to the surrounding tissue. The warming leads to increased blood circulation and relaxation of the muscle tissue and, as a result, to a decrease in pain. Again, there should be no additional inflammation in the arthrotic joint.
For some years now, acupuncture for knee arthrosis has also been reimbursed by the statutory health insurance companies. A positive effect has been scientifically established. If no improvement of the inner knee pain can be achieved with conservative measures, a mirror image of the joint with repair of the damaged joint cartilage can be considered in the further course of treatment.
One possibility is microfracturing of the bone exposed by the cartilage loss. The doctor drills a few small holes in the bone during the endoscopy. These defects are then filled up again by the body.
Since the bone is well supplied with blood, stem cells are also washed out with the blood. From these, new replacement cartilage can develop, but it cannot compete with the original cartilage in terms of resilience. Another possibility is the cultivation of new cartilage cells.
For this purpose, a piece of cartilage is removed during an initial endoscopy, which is then multiplied in the laboratory within one to two months. It is then reinserted into the joint during a second endoscopy. This procedure can also be used to cover larger defects.
A third alternative for rather small cartilage defects is the relocation of a cartilage bone cylinder. A punch of cartilage and bone is taken from an area of the joint that is only slightly loaded. The cylinder is then fixed in the main load zone as a replacement.
All three methods of cartilage replacement are particularly suitable for younger patients in order to delay the time until the joint is replaced. At the same time, an arthroscopy of the knee joint can be performed. During this procedure, disturbing mucous membrane folds or bony attachments (osteophytes) can be removed, which can cause severe pain in addition to cartilage abrasion.
The last stage of arthrosis treatment is surgery. Especially in younger patients up to 60 years of age with an axial malposition of the legs (in our case bow legs), a repositioning osteotomy is promising. The bow legs cause unilateral arthrosis on the inside of the knee joint, which also explains the increased inner knee pain.
In an osteotomy, the tibia is cut through below the knee joint and then stretched until the leg axis is slightly X-leg shaped. The resulting gap is filled with bone from the iliac crest or artificial bone and then fixed with plates and screws. After the operation, the leg must be relieved for six weeks with crutches and mobilized with the help of physiotherapists.
During this time, the leg can be slowly regained full weight-bearing under supervision. After about a year, the metal parts are removed from the leg in a small operation. Another surgical option is joint replacement.
This is aimed at when the patient’s pain cannot be relieved by other means and the quality of life is reduced by the restriction of mobility. A small form of joint replacement is the unicondylar sled prosthesis. This prosthesis is characterized by its size.
It replaces only the affected inner part of the knee joint, which is removed during the operation and replaced by a metal and plastic prosthesis. Another advantage is the faster rehabilitation after the operation. The prerequisites for a sled prosthesis are a stable ligamentous apparatus, no axial malposition of the leg and no excessive physical activity.
If these requirements are not met or the remaining knee joint already shows arthrotic changes, a total endoprosthesis (knee TEP) is the better choice. With a total endoprosthesis, both the upper part of the knee joint, which is actually formed by the femur, and the lower part of the knee joint, which is the tibial head, are replaced.The bone parts are straightened and the prosthesis parts are anchored with small wedges and bone cement. After each form of prosthesis implantation, a rehabilitation is carried out in order to achieve complete mobility under professional guidance and to be optimally prepared for everyday life.
The prognosis of a knee TEP is good. It lasts up to 20 years and allows a painless full functionality of the knee joint.
